IL33563A - 1,2-dihydrotriazines and their use as herbicides - Google Patents

Description

1,2-Dihydrotriazines and their use as herbicides ROHM AND H'AS COMPANY 0.31745 This invention is concerned with new and useful organic chemical compounds of the class of 1 , 2-dihydrotriazines and their use as herbicides.

The invention also embodies various herbicidal . formulations and compositions and their employment in the control of undesirable plant growth.

The novel compounds of this invention are 2-one or 2-thione derivatives of l-alkyl-4-alkylamino-1 , 2-dihydro-l , 3, 5-triazines. These may be depicted by the following structural . formula wherein R is an alk l group of 1 to 5 carbon atoms, R 2 is an alkyl group of 1 to 14 carbon atoms, R3 is hydrogen, methyl or ethyl and X is 0 or S.

The alkyl groups can be straight or branched 2 chain. Typically, the R alkyl groups may be methyl, ethyl, propyl, isopropyl, butyl, t-butyl, amyl, octyl, t.-octyl (i.e., 1 , 1 , 3 , 3-tetramethylbutyl ) , decyl and Jt-dodecyl, with the tertiary alkyl groups being 3 preferred. The compounds where R is hydrogen are preferred.

For convenience these compounds are sometimes rei srred ' to below as simply 1 ,2-dihydro-l , 3 , -triazines.

The chemistry of symmetrical-triazines and the her b:. - . ■ cidal properties of selected members of this class of compounds . are widely known. Such herbicidal structures include 2>-chloro- H-, 6-bis(ethylamino) -si-triazine (simazine) , 2-chloro-l+-ethylamino- 6-isopropylamino-s.-triazirie (atra..ine) , 2-methoxy-1+, 6-bis(iso- propylamino)-s.-triazine (prometone) and 2 , ½-bis(isopropylamino) - 6-methylmercapto-s_-triazine (prometryne), for which see Herbicide- Handbook of the Weed Society of America, First Edition 1967 , pages .21 , h2, 6 and 191. The chemistry of the 1 , 2-dihydro-l , 3 , 5-triazin - 2-one and triazine-2-thione is much more obscure and their herbicidal properties have not been investigated. Such compounds having a ^-amino substitutent and a 6-alkyl substituent have been reported by Ostragovich et al. (see Chemical Abstracts 6 , 1137 (1912) , 2 , 70 (1931 ) and 10 , >+68 (1936) ) , by Dangyan and Titanyan (see Chemical Abstracts 5!t> 561 (I960) ) and by Kreutzberger (see J. Am. Chem. Soc. 22., 2629 (1957 ) ) . These structures having 1-alkyl-^-amino -6-alkyl substitutents have . been -studied by Piskala and Gut (see Chemical Abstracts 52.) 7529 (1963 ) ) and those with a >+-alkylamino substituent have been reported in German Patent 1 ,065) 687. The l-alkyl-^-alkylamino and the 1-alkyl-*+-alkylamino -6-alkyl derivatives have not heretofore been investigated. 0ne general method of preparation is the reaction of an alkyl guanidine with an alkyl isocyanate or isothiocyanc e to produce the corresponding . alkylcarbamoyl or alkylthiocarbamoyl guanidine and this is then condensed with ah ortho ester to close In these formulas R , R , RJ and X have the meanings given above.

The starting alkyl guanidines of Formula I, often in salt form, may e made by known methods such as reaction of a thiuronium salt with a primary amine (R NH2) or by the method of U..S. Patent 3»llt »231. by reaction of the alkyl cyanamide (R¾HCN) with ammonium chloride.

The reaction of the alkyl guanidine with the isocyanate or isothiocyanate (R½CX) is preferably carried out in the presence of. a solvent such as ketones, e.g. acetone, dioxane and dimethyl sulfoxide. Often a salt, such as the hydrochloride, of the alkyl guanidine is used and this is neutralized with a base such as alkaline hydroxide or alkaline alkoxide to free th . with the R NCX compound may conveniently be carried out in the temperature range of 20°-60° C, preferably 35°-l+50 C. In some instances a slight exotherm occurs and the temperature may be maintained by the regulated addition of one reactant to the other. The order of. addition is not critical. The. reaction is usually fairly rapid. The products are isolated by conventional means such as precipitation by drowning in water, filtration and recrystallization. A literature reference which describes the general method of preparation of carbamoyl derivatives of guanidines is F.H.S. Curd et al J.- Chem. Soc. 19'-9. 17 '2. A related reaction of amidines with isothiocyanates is described in A; Pinner "Die Imidather und Ihre Derivate", Berlin 1892, page I69. Table I gives the characterization of compounds of Formula II.

The ring closure of the compounds of Formula II by means of ortho esters has been used for related dihydrotriazines. For example see Piskala and Gut, Chemical Abstracts .£2., 7529c (1963). Shapiro et al., e.g. see J. Am. Chem. Soc. 8l, 2220 (1959)» describe this method for1 the preparation of triazines from biguanides . For this reaction use of an excess of the ortho ester as a solvent is preferred. The reaction is often run at reflux temperature and, because of the lower boiling point, a methyl ortho ester is often preferred to an ethyl ortho ester.

The reaction temperature is usually in the range of 1+0°-120° C, preferably 50°-100° C. The ring closure may be somewhat slow and often requires 20 hours or more. An acid catalyst facilitates the reaction. Typical acid catalysts are p-toluene sulfonic acid and a macroreticular sulfonic acid ion exchange resin.

It is often convenient to remove the excess ortho ester under vacuum and to reuse it. The product thus obtained as a residue may be purified, if desired, by conventional means such as recrystallization.

An alternative reagent. for cyclization which can be used is dimethylformamide dimethylacetal without solvent. In certain cases superior yields are obtained with this reagent. > In some instances the ring closure of the thiocar-bamoyl guanidines of the formula • NH S R2NH -<ϋ -1— NH C NHR1 results in at least partial hydrolysis of the thione group and a l,2-dihydro-l,3)5-'triazin-2-one, i.e. a compound of Formula III -wherein X is .0, results.

Method I is best suited to ^--alkylamino derivatives in which the alkyl group is sterically hindered, e.g. t.-butyl or t.-octyl. For ½-alkylamino derivatives in which the alkyl group . is less sterically hindered, alternative syntheses are preferable, utilizing the isobiurets. Thus, methyl isothiourea is condensed with an alkyl isothiodyanate and the l-alkyl-—S-methylisodithio-biuret formed is cyclized, as by trimethyl ortho-esters. intermediate reacts with -amines to give the desired triazines in an overall reaction scheme analogous to that described by Piskala and .Gut (loc. cit) and diagrammed below as Method II.

Method II ·■'.; . '· ' · '. . . :■ ■■': : ■ NH R½CS + NH^CSCH, : — > 3 salt of the isothiourea, such as the sulfate, is used and this is neutralized with a base, such as an alkali hydroxide, carbonate, bicarbonate or alkoxide to free the base, preferably just prior, to the reaction with the alkyl isothiocyanate.. The reaction may be conveniently carried out in a temperature range of -10° to 60° C, preferably 0° to 5° C. In some instances it is preferable to. add the base in the minimum volume of water to a mixture of the alkyl isothiocyanate and the isothiourea in a solvent. A procedure for an analogous reaction is described in Organic Syntheses ½2, .87.. \ The reaction of the alkyl isocyanate with thiourea is conveniently carried out in a solvent such as dimethylformamide by heating a mixture of the' two reagents at 50°-150° C.a preferably 80°-100° G., for 1-30 hours. The 1-alkyl-^-thiobiuret may be conveniently isolated by drowning in water, filtration and . recrystallization. Quaternization of the 1-alkyl-^--thiobiuret is achieved by heating with, one equivalent of benzyl chloride in a solvent such as dimethylformamide for 1-30 hours. The hydrochloride may be isolated by removal of the solvent and precipitation with ethyl acetate. The free base obtained by treatment with bases, such as aqueous sodium hydroxide, is cyclized as described for Method I. 2 Displacement of the M—benzylthio group with the —NHR group is effected by heating under reflux in benzene with at least one equivalent of the desired amine in the presence of an acid catalyst, such as JD-toluenesulfonic acid. Sterically hindered alkyl. amines do not react under these conditions.

In certain cases it may be preferable to synthesize the oxygen analogue (Formula V) from the sulfur analogue (Formula IV) by reaction with metal oxides or oxidizing agents , e.g. mercuric oxide or basic hydrogen peroxide. ■ . · , b) Preparation of l-ethyl-^-S-benzylisothiobiuret 2-one. 1-Ethyl-^-benzylthio-1 , 2- dihydro-1 , 3 , 5-triazin-2-one (17 g., 0.0688 mole) was dissolved in benzene (60 ml.) and heated under reflux 2-3 hours with n-butylamine (l* g. , 0.192 mole) and ^.-toluene-sulfonic acid (300 mg.). The solvent was removed under reduced pressure and the residue was recrystallized from ethyl - -·.,· 66$ yield of l-et l-Lι-n-b t lamino-l,2-dihydΓO-l,3 , 5- Γiazin- 2-one.

Example 7 Preparation of 1-ethyl-^--n-butylamino- 1 < 2-dihydro-l , 3 < 5-triazine-2-^thione a) Preparation of l-ethyl-^-S-methylisodithiobiuret To a mixture of 50$ sodium hydroxide (92 g., 1.15 mole), water (200 ml.) and acetone (300 ml.) at -20° C. was added 2-methyl-2-thioisourea sulfate (160 g., 0.575 mole). Ethyl isothiocyanate (100 g., 1.15 mole) was then added and the mixture was stirred at -20° C. for 30 minutes and then allowed to warm slurry was minutes and was then cooled to give three phases. The top organic phase was separated and concentrated under reduced pressure to give a ' residue which was extracted with benzene. The solvent was removed leaving a 120 g. residue of amber oil. This was a mixture of 1-ethyl -—S-methylisodithiobiuret with impurities which do not interfere with the subsequent cyclization. b) Preparation of.1-ethyl-t -methylthiom,2-dihydro-l, 3 , 5-triazine- 2-thione.

The concentrate from Part a) above (70 g. of purity, 0.25 mole) was heated .with trimethyl orthoformate (1^5 g«> 1.25 mole) and 0.9 g. of ja-toluenesulfonic acid at 90°-95° C. for 3 hours. Upon cooling, crystals separated and these were purified by recrystallization from ethyl acetate. The solid, melted at 16^-166° C. It was found to contain 38.8$ C, 5.0$ H, 22. 5$ and 33 - 2 S; calculated for is 38.5$ C, k.8% H, 22A% and 3^.2$ S. The product is 1-ethyl -methylthio-1 , 2-dihydro-l , 3 > 5-triazine-2-thione . c) Preparation of 1-ethyl-^--n-butylamino-l, 2-dihydro-l, 3 , 5- triazine-2-thione . (3 · 9 g'j -0.0 35 mole) for 30 minutes until evolution of methyl mercaptan had practically ceased. On cooling, crystals separated and were filtered off, washed with benzene and air dried to 5· 5 g. This was a k % yield of 1-ethyl-^-n-butylamino- l, 2-dihydro-l, 3 , 5-triazine-2-thione.

¾ Examples 10 and 11 - Preparation of 1-ethyl-^-t-butylamino-l , 2- dihydro-1 , 3 « -triazine-2-thione a) Preparation of N-£-butyl-N ' -(ethylthiocarbamoyl)guanidine.

. A solution of 30 g. (0. 2 .mole) of t.-butylguanidine hydrochloride in 300 ml. of dioxane and 30 ml. of water was made basic by the addition of 17 g. ( 0. 21 mole) of $0% aqueous sodium hydroxide. To. this was added dropwise over a period of 1? minutes 19 · g.- (0. 22 mole) of ethyl isothiocyanate. The reaction mixture was stirred about 30 minutes at h00- 5° C. and was then poured into 1 1. of ice water. The resulting solid was isolated, dried and recrystallized from toluene to give 22. 5 g' of white solid. Its infrared spectrum corresponded to the structure of N-t.-butyl-N '-(ethylthiocarbamoyl )guanidine . b) Ring -closure with an orthoformate.

A mixture of 15 g. (0.0 ^ mole) of N-t-butyl-N · -(ethylthiocarbamoyl)guanidine, 53 g. (0. 5 mole) of trimethyl* -orthoformate and 0. 5 g.-of p_-toluenesulfonic acid mpnohydrate was stirred at 70°-80° C. for 30 hrs.' Upon cooling to room tempera-ture 9 g» of solid was isolated and, after recrystallization from ethyl acetate, this amounted to 7 g. yield) of l-e,thyl->+-t-butylamino-l, 2-dihydro-l, 3 > 5-triazine-2-thione. \ c) Conversion of 1-ethyl-½-jt-butylamino-l, 2-dihydr.o -1 , 3 , 5-triazine 2-thione to its oxygen analog.

An alcoholic solution of 1-ethyl-^-i-butylainino-l , 2- dihydro-l, 3 , 5-triazine-2-thione was heated at reflux' temperature ' 5 overnight Llth five equivalents of mercuric oxide. A good conversion to 1-ethyl-1+-t.-butylamino-l, 2-dihydro-l, 3 , 5-triazin- 2-one resulted. .. x ·.

Example 18 ■■ \ ■ '. ' · - '— Preparation of .l-n-butyl-'i-t-octylamino-l^-lO dihydro-1 , -triazin-2-one. ■· .

A mixture of 8 g. (0.028 mole) of N-t-octyl-N ' -(butyl- thiocarbamoyl)guanidine, +3 · g. (0 05 mole) of trimethyl ortho^ .. .. . * ■ \ ' formate and 0.5 g. p_-toluenesulfonic acifl was stirred 2^ hrs.. at 95°-98° C. The reaction mixture was' cooled and poured into 500 ml • \ of ice; water. A waxy precipitate was isolated and dried on a . /' V porous plate to give 6.8 g of solid which was purified by ' recrystallization from hexane to give g« » melting point 98°- . 100° C. Analysis proved the compound to be 1-n-butyl octylamino-1 , 2-dihydro-l, 3 , 5-triazin-2-one; thus, showing that hydrolysis of the sulfur atom had occurred under the reaction conditions.

Examples 21 and 22 Preparation of 1-methyl-½-t-butylamino-6-ethyl-l, 2-dihydro-l, 3 , - triazine-2-thione and its oxygen analog. \ A mixture of 18.8 g. (0.1 mole) of N-t-butyl-N ' - '.'·'■ . ,..'· (methylthiocarbaraoyl)guanidine, 80 g.. (0.5 mole) of triethyl orthopropionate and 1 g. of ,p_-toluenesulfonic acid monohydrate was heated at 55°-60° C. for 20 hrs. The reaction mixture was then dissolved in toluene, washed three times with water, dried 0 · oyer magnesium sulfate and the solvent removed.- The residue was triturated with ether to give k.2 g. of a solid melting at 1^-2° τ 151° C. and this, after recrystallization from alcoholjwas 2 g. of a white solid' melting at 150°-153° C. This was 1-methyl -k- 1-butylamino-6-ethyl-l , 2-dihydro-l ,3 , 5-triazine-2-thione .

The alcohol filtrate was evaporated to give 1.6 g. of light yellow solid which was l-methyl-i+-t,-butylamino-6-ethyl-l, 2-dihydro-1 , 3 , 5-triazin-2-one .

Example 26 Preparation of 1-n-butyl -k- 1-octylamino -6-methyl -1 , 2-dihydro -1 , 3 » • triazine-2-thione A mixture of 15 g. (0.052 mole) of N-t.-octyl-N* - (butylthiocarbamoyl)guanidine, 60 g. (0.5 mole) of trimethyl orthoacetate and 0.5 g. of p_-toluenesulfonic acid monohydrate was heated at 60°-70° C. for 20 hrs. The reaction mixture was dissolved in 300 ml. of toluene, washed three times with water, dried over magnesium sulfate and the solvent removed. The residue was dissolved in ether and cooled to give k g. of a white solid melting at 122°-12½° C. Recrystallization from methylcyclohexane did not change the melting point. The solid was l-n-butyl-^-t.-octylamino -6-meth 1-1 , 2-dihydro-l , 3 , 5-triazine-2-thione.

Table III (Continued) Example Melting Empirical No. Point (°C.) Formula C H . 151-153 C12¾2¾° 60.3 (60,5) , i 9.3 ( 9.3 16 1^2-1^5 C12H22V 56.5 (56.6) 1 8.8 ( 8. 17 124-126 ¾¾ A° 61.5 (61.9) 9.9 ( 9.6 18 98-100 °15Η28¾0¾ 6t.l '(6 .2) 10.2 (10. 19 "82-83 c15¾8¾s 60.7 (60.8) 9.7 ( 9. · 176-179 C9H16¾S 51.3 (50.9) ' 7.6 ( 7.6 21 165-168. , .56.9 (57.1) 8.6 ( 8.6 22 150-153 C10H18¾S 52 (52.9) .7.6 ( 7. 23 115-117 C13¾AS ' 58.1 (58.2) 8.9 ( '9. 108-110 Cll¾6V ' 60. h (59-5) 9.3 ( 9-3 108-110 C15¾8¾S 60.7 (60.8) 9.7 (9-5) 26 122-12^ C16H30V 62.0 (61.9)· 10.0 (9.7) . 27 126-128 C17¾2Nl+S 60.3 (62.6) 10.0 (9.

The number in parenthesis represents the theoretical value =analysis for oxygen The l,2-dihydro-l,3, -triazines of this invention possess biocidal properties and in this respect are particularly useful as herbicides. The most, active of these compounds possess both preemergence and postemergence. herbicidal properties For such purposes these compounds are most often used as solutions or formulations so as to render them suitable for subsequent dissemination as herbicides. For example the 1,2-dihydro may be formulated as wettable powders, emulsi- fiable concentrates , dusts5 granular formulations, aerosols or flowable emulsion concentrates. In such formulations, the compounds are extended with a liquid or solid carrier and, when desired, suitable surfactants are incorporated. ■ It' is usually desirable, particularly in postemergence applications, to include adjuvants, such as wetting agents, spreading agents, dispersing agents, stickers, adhesives and the like. in accordance with agricultural practices. Such adjuvants commonly used in the art may be found in the John W. McCutcheon,' Inc. publication "Detergents and Emulsifiers 196? Annual".

Numerous polymer latices or aqueous dispersions, particularly those in which the polymers per se exhibit some degree of tack, will also function effectively as adherent or sticking agents. Typical of such compounds are homo-, co-,. or terpolymers of a wide variety of vinyl monomers, particularly combinations of acrylate and methacrylate esters, vinyl acetate, vinyl chloride, styrene, butadiene, isoprene, etc. Terpolymers containing acrylate and methacrylate esters and a minor proportion of acrylic and methacrylic acids are .lso ver effective. The compounds of this invention may also be combined with agricultural oil's such as refined mineral oils.

The compounds of this invention may be dissolved in an.. appropri alcohols, ketones, aromatic hydro- ' ' tration of the solution may vary from 2% to 98 , with a preferred range being 25% to 75%> For the preparation of emulsifiable concentrates, the compound may be dissolved in organic solvents, such as xylene, pine oil, orthodichlorobenzene, methyl oleate, or a mixture of solvents, together with an emulsifying agent which permits dispersion in water. The concentration of the active ingredient in emulsifiable concentrates is usually.10% to 2 % and, in. flowable . emulsion concentrates, this may be as high as 75%> ■ "Wettable powders suitable for spraying 'may be prepared ' · · ' !-..--' by admixing the compound with a finely divided solid, such as clays, inorganic silicates and carbonates, and silicas' and incorporating wetting agents, sticking agents, and/or dispersing agents in such mixtures. The concentration of active ingredients in such formulations is usually in the range of 20% to 98$, preferably h0% to 75%.

Dusts are prepared by mixing' the compounds of this in- vention. with finely divided inert solids which may be organic or inorganic in nature. Materials useful for this purpose include botanical flours, silicas, silicates, carbonates and clays. One • convenient method of preparing a dust is to dilute a wettable powder with a finely divided carrier. Dust concentrates containing . 20% to 80$ of the active ingredient are commonly, made and are . subsequently diluted to 1% to 10% use concentration.

■ ' Tne l>2-dihydro-l,3,5-triazines .can be applied as herbi- cidal sprp.ys by methods commonly employed, such as conventional high-gallonage-hydraulic sprays, low gallonage sprays, airblast • spray, aerial sprays and dusts. For low-volume applications a solution of the compound is usually used.. The dilution and rate of application will depend upon such factors as the type of equip amount is. usually in the range of 0.25 lb. to 2 lbs. per acre of the active ingredient. / The l, 2-dihydro_-l, 3 > 5-triazines of this were . evaluated for herbicidal activity/in standard herbicide screening · procedures. \ In one such test seeds of selected crops and weeds were planted in soil in pots. For preemergence tests these pots were \ treated immediately with the test compound. For postemergence tests the seeds were allowed to germinate and the plants to grow for two weeks, at which time, they were .treated by foliar application or by drenching the soil with the test chemical. For these preliminary tests 150 mg. of the test . compound was dissolved in ml. of acetone. Ten ml. of this solution was diluted to 250 ml. with water and this was used to drench the soil in the pots con- stituting the preemergence test. For the foliar postemergence test 10 ml. of the stock solution was, uniformly sprayed onto the postemergence pots. For a drench postemergence test 10 ml. of the stock solution was diluted to 250 ml. with water and this was poured onto the soil around the base of the growing plants in the postemergence pots. In all cases the toxicant amounts to about lbs. per acre. Four types of monocotyle.donous plants were used and these were millet (Setaria italica), ryegrass (Lolium perenne), sorghum (Sorghum vuleare) and wild oat (Avena fatua) . Four types of dicotyledonous plants were used and these were curly dock (Rumex crispus) , flax (Linum usitatissimum) , tomato (Lycopersicum . esculentum) and velvetleaf (Abutilon theophrasti) . About 2 weeks after application of the candidate herbicidal agents, the state of growth and the phytotoxic effects were evaluated. Table IV gives the average percent control for the monocotyledonous (Mono) and the dicotyledonous (Di) plant species. lover application rates (pounds per acre, lbs. /A). In these tests flats were sprayed using a carrier volume of 50 gallons per acre. The plant species involved were: Monocotyledons A' . barnvarderass . (Echinochloa crusgalli)' B corn (Zea maize) . C foxtail (Setaria faberii) D. ., • - millet (Setaria italica) . " E . rice (Oryzae sativa) ·' F rveerass (Lolium perenne) G Sudanerass (Sorghum sudanensis) H ' wheat (Triticum vulgare) I wild oat (Avena fatua) Dicotyledons " J alfalfa (Medicaid sativa) cotton (Gossvpium hirsutum) "' L curlv dock (Rumex crispus) M ' flax (Linum usitatissimum) . N lambsquarters (Chenopodium album) •0 mustard (Brassica kaber) ■'" p ' pieweed (Amaranthus retroflexus) soybean (Glycine max) R tomato (Lycopersicum esculentum) . S ' velvetleaf (Abutilon theophrasti) • T wild carrot (Daucus carota) Table V gives the percent control of the various plant species (designated by the letter identification given above) for several examples of the .l,2-dihy.dro-l,3,5-triazines.

Table IV Herbicidal" Evaluations on 1 , 2-Dihvdro-l < . -triazines Control at 10 lbs./A Treatment Plants Preemergence Postemergence .-Example Spray Drench • 1 Mono' ■ · . 68 95 95 ■ Di 85· 98 , 100 2- ' Mono · 0 ·' ·'. ■ '·" 5" Di 0 ' 80 · ' If. Mono o . ·. 80 . Di 22.·■■■" ,.. 100 : Mono . . 0 80 . ' Di · . 20. 100 ; 6 Mono 0 52 . 0 92 7 Mono 0 ko': . Di o. 82' : 8 Mono 5 80 Di 18 100 Mono 0 ' ■ ■ ' ■" k2 ■ ■ Di 0 98 :.v Mono . 70 95 * 97 Di ■ . 95 100 100 11 Mono ■ - 85 92 100 Di ·; 92 . 100 . 100 12 Mono • 0- 38 0 Di 0 . . 95 90 ■ ■ 13 Mono . 82 92 75 Di- 8o ' . 100 98 ■ ! . . Mono ■ 10 . ' 18 . 12 Di • 0 ; 78 78 ■ . Mono 8 30 5 Di . 20 .60 ·· 15 ■ 16 Mono 18 · 28 . 20 Di · . 28 .62 20 .. • 17 Mono 22 ' 22 5 , Di k8 .- 92 18 Mono 0 18·' 0 Table IV (cont. )' % Control at 10 lbs. /A Treatment Plants Preemergence Postemergence . Example Spray : Drench Mono .. . 0 22' 0 : Di 0 60. 0 Mono 0.' . 28 ' 0 Di. ■ 10 ' 62' ' · 22 Mono 0 ■ 18 . . .... 0 , . Di 2 ho 0 23 Mono 0 ' 15 , 0 ' Di ... 0 ' 58 .0 ■ Mono . 0 ' '. 10 .0 • 0 • 30 .. 0 . Mono 0 10 0 Di 0 60 ' 4 o 26 Mono 0 ' 35 ' . 0 Di 0 8o o 27 ; Mono 0 , 8 '· 0 " ■ Di, 0 22 0 ! In some instances it may be desirable to add one or' more other pesticides. Other herbicides which can be in¬ 2,3 ,6-trichlorophenylacetic acid and its salts 3 ,6-endoxohexahydrophthalic acid dimethyl 2,3}5}6-tetrachloroterephthalate trichloroacetic acid and its salts ■ 2.2-dichloropropionic acid and its salts 2.3-dichloroisobutyric acid and its salts . . k-( 2-methyl-~chlorophenoxy)butyric acid and its salts and esters · Substituted Triazines 2-chloro-1+, 6-bis ( e hylamino ) -s.-triaz'ine ' \2-chloro-^-ethylamino-6-isopropylamino-s.-triazine 2-chloro-Lh,6-bis(methoxypropylamino) -s.-triazine 2-methoxy-lh,6-bis (isopropylamino ) -s-triazine 2-chloro-i+-ethylamino-6-(3-methoxypropylamino) -s.-triazine 2-methylm^oroapto-^,6-bis( isopropylamino) -s.-triazine .2-methylmo¾oap o-1+,6-bis(ethylamino)-s.-triazine 2-methylmoroapto-1+-ethylamino-6^-isopropylamino-s.-triazine 2-chloro-1+,6-bis(isopropylamino) -s-triazine 2-methoxy-!+,6-bis( ethyl a. m ino) -s.-triazine 2-methoxy-1+-ethylamino-6-isopropylamino-s.-triazine 2-methylin^oafito-h-(2-methoxyethylamino 6^isop.ropylamino- s.-triazine Diphenyl Ether Derivatives · 2,^-dichlqro- -nitrodiphenyl ether 2,1+,6-trichloro-Lf-, -nitrodiphenyl ether . . ' ' 2,^-dichloro-6-fluoro- -nitrodiphenyl ether ,· 3-methyl->+ ' -nitrodiphenyl ether ' . ·,· 3 , ^-dimethyl-^- 1 -nitrodiphenyl ether 2, k 1 -dinitro-^-trifluoromethyldiphenyl ether ' Anilides ,-N-(3',^-dichlorophenyl)propionamide N-(3 ,Ή—dichlorophenyl )methacrylamide ·'..;..· N-(3-chloro-5+-methylphenyl)-2-methylpentanamide N-(3 ,*+-dichlorophenyl) trimethylacetamide N-(3 )^-dichlorophenyl)- ,a-diuethylvaleramide...

■ ' ■ ' Other Organic Herbicides ', 2-chloro-N,N-diallylacetamide N-(l ,1-dimethyl-2-propynyl ) -3 , 5-dichlorobenzamide maleic hydrazide 3-araino-l ,2,½-triazole . monosodium methanearsonate disodium methanearsonate N,N-dimethyl-a, a-diphenylacetamide ■ N ,N-di-(n-propyl ) -2, 6-dinitro-1+-methylaniline N ,N-di(n-propyl) -2, 6-dinitro-1+-methylsulfonylaniline 0-(2,1+-dichlorophenyl)-0-methyl-isopropylphosphoramido- thioate ' amino-3,5)6-trichloropicolinic acid 2 ,3-dichloro-1 ,^--naphthoquinone di(methoxythiocarbonyl)disulfide 6,7-dihydrodipyrido[l , 2-a :2 ' ,11 -c]pyrazidinium salts 1,1 ' -dimethyl-ϊ+,ϊ+' -bipyridinium salts 3 Λ> 5>6-tetrahydro-3 , -dimethyl-2-thio-2H-l ,3 , 5-thiadiazine This invention provides new compounds which are

Claims (11)

What we claim is:

1. A compound of the formula wherein is an alkyl group of 1 to 5 carbon atoms, R 2 is. an alkyl group of 3 1 to 14 carbon atoms, R is hydrogen, methyl or ethyl and X is 0 or S.

2. A compound according to Claim 1 wherein is methyl. 1

3. A compound according to Claim 1 wherein R is ethyl. 4o A compound according to Claim 1 wherein is isopropyl .

4. . A compound a 2

5. Ccording to Claim 1 wherein R is tertiary butyl. 3

6. A compound according to Claim 1 wherein R is hydrogen.

7. A herbicidal composition comprising a carrier and a compound according to any one of Claims 1 - 6.

8. A herbicidal composition comprising a compound according to any one of Claims 1 - 6 and a surfactant or finely divided solid diluent.

9. A composition according to Claim 8 in the form of an emulsifyable concentrate, an emulsion concentrate, dust or wettable powder.

10. A composition according to Claim 7 in the form of granules.

11. A method for controlling undesirable plant growth which comprises applying to the area to be controlled a growth regulating amount of a compound of the formula HNR wherein R is an alkyl group of 1 to 5 carbon atoms, R 2 is an alkyl group of 1 to 14 carbon atoms, R3 is hydrogen, methyl or ethyl and X is 0 or S. For the Applicants DJ. R s '. IOLt)/ Q